The Glyceryl Diesters act as lubricants on the surface of the skin, which gives the skin a soft and smooth appearance.

Scientific Facts:

The Glyceryl Diesters are prepared from fully refined vegetable oils. Specific fatty acids are obtained from this process and are reacted with glycerin to yield the individual diglyceride. For example, Glyceryl Dilaurate is produced from glycerin and lauric acid; Glyceryl Distearate is produced from glycerin and stearic acid. Glycerin has three carbon atoms. The fatty acids in these diesters are generally bound to the first and third carbon atoms of glycerin, although there may be small amounts of diester with the fatty acids bound to the first and second carbon atoms.

Safety

Safety Information:

The Food and Drug Administration (FDA) reviewed the safety of Glyceryl Diesters (Diglycerides) and approved their use as indirect food additives. Mono- and diglycerides are affirmed Generally Recognized as Safe (GRAS) direct food ingredients. They are often blended together and added directly to food. The safety of the Glyceryl Diesters has been assessed by the Cosmetic Ingredient Review (CIR) Expert Panel.

CIR Safety Review: CIR The Expert Panel considered that the available safety test data indicated that diglycerides in the 1,3-diester form do not present any significant toxicity risk, nor are these ingredients irritating, sensitizing or photosensitizing. Whereas no data were available regarding reproductive or developmental toxicity, there was no reason to suspect any such toxicity because the dermal absorption of these ingredients was negligible.

The CIR Expert Panel noted that depending on the chain length and structure, the 1,3-diglycerides might contain some 1,2-diglycerides. Some 1,2-diglycerides, especially those with carbon chains less than 14 in length and mixed saturated/unsaturated fatty acids, may have a tumor promotion potential.

With the exception of Glyceryl Dilaurate, with 12 carbons in both fatty acid chains, the diglycerides considered in this safety assessment have at least one fatty acid chain of 14 carbons or longer and none have mixed saturated/unsaturated fatty acid moieties. Glyceryl Dilaurate was a mild primary irritant, but not a skin sensitizer in maximization tests.

An eye shadow containing 1.5% Glyceryl Dilaurate did not induce skin irritation in a single insult patch test, but mild skin irritation reactions to a foundation containing the same concentration were observed. A trade mixture containing Glyceryl Dibehenate did not induce irritation or significant cutaneous intolerance in a 48 hour occlusive patch test. In maximization tests, neither an eye shadow nor a foundation containing 1.5% Glyceryl Dilaurate was a skin sensitizer. Sensitization was not induced in subjects patch tested with 50% Glyceryl Dioleate in a repeated insult, occlusive patch test. Glyceryl Palmitate Lactate (50%) did not induce skin irritation or sensitization in subjects patch tested in a repeat insult patch test.

The CIR Panel considered it important that a 21-week use study of a prototype lotion containing 0.5% Glyceryl Dilaurate (a 12-carbon chain fatty acid) indicated no evidence of scaling, inflammation, or neoplasms in biopsy specimens. Also, DNA synthesis assays on Glyceryl Dilaurate and Glyceryl Distearate indicated that neither substance altered cell proliferation (as determined by DNA synthesis) in normal human dermal fibroblasts in vitro at doses up to 10 microg/ml.

Link to FDA Code of Federal Regulations for Fatty Acids reacted with Glycerin (mono- and diglycerides) and Mono- and Diglyceride mixtures

These ingredients are 1,3-diglycerides, depending on the chain length and branching, some can be isomerized to the 1,2-diglyceride form. In cosmetics and personal care products, Glyceryl Diesters are used as skin conditioning agents - emollients.

Resources

Resources:

Find out more about the regulation of Food Additives by the Food and Drug Administration